When not in use, mobile communication devices such as cell phones or PDAs are typically carried in pockets, briefcases or handbags. Often the devices are bumped or jarred during transportation causing device input, such as keystrokes or touchscreen selections, to occur inadvertently. This device input can result in unintentional phone calls being made, corruption of data or battery drainage.
In order to reduce the occurrence of inadvertent device input, many mobile communication devices include a lock mode in which keystrokes or touchscreen selections are not registered. The lock mode is enabled and disabled in different ways depending on the type of device. For example, the lock mode may be enabled by pressing and holding a particular key or touchscreen icon, by pressing a particular key or touchscreen icon twice in succession or by sliding the device into a carrying case of some sort. Similarly, the lock mode may be disabled by pressing and holding the same key or touchscreen icon that locked the device, by pressing a key or touchscreen icon that launches an “unlock” menu option on the display screen of the device, or by removing the device from a carrying case.
The existing lock mode enabling/disabling methods typically consume extra time because the user often looks for a visual confirmation that the action has been successfully completed on the display screen. In addition, some existing methods are difficult to execute if the user is not looking at the device.
Pressing and holding a key or touchscreen icon for a specified amount of time does not provide any user feedback and typically results in the user checking the display screen in order to confirm that the action has taken place. In addition, if the lock/unlock selector is part of the keypad or is one of a group of touchscreen icons, blind identification may be difficult and the user may be reluctant to perform the locking/unlocking action without looking at the device.
Devices that include different input combinations assigned to enabling and disabling the lock mode require additional learning since the user must remember a different set of keystrokes or touchscreen selections for each. Again, the user would typically look at the device while enabling or disabling the lock mode or shortly thereafter in order to confirm that the action was performed successfully.